I am using FreeCAD for about 3 years mainly for the design of r/c sailboats. Last year I started to have a closer look on OpenFOAM. After some help by @thschrader who put me on the right track I was able to produce nice pictures and I got first results which helped for my construction work. Last week I got some experimental data and I could verify a set of simulations for the first time. Now I am pretty sure that I am making not too much nonsense. Thanks to @thschrader for his help.
So far so good. Now I have a problem with the user interface. To calculate the friction I need access to the wall shear stress. I found several tutorials how to use this function, I found the right dictionary where to activate it, but I have no clue what parameters or other modifications are needed. I tried also the pisoFoam solver. The result is always the same. The simulation runs well, but no wallShearStress array is accessible. Something is wrong and I have no clue where to look for a mistake. The documentation I found is poor (or I am missing too much background information to understand it). I also found no possibility to activate the wallShearStress from CDoF.
I have installed the blueCFD-Core-2020-1-win64 package on the FreeCad 0.21.0.31625. OS is an up-to-date WINDOWS 11 (not 10 as shown by the FC Info below. But it was the same with Win10). The modified controlDict File is included below.
I would be very happy if somebody could help.
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/*--------------------------------*- C++ -*----------------------------------*\
| |
| Generated by the CfdOF workbench for FreeCAD |
| https://gitlab.com/opensimproject/CfdOF |
| |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
object controlDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
application simpleFoam;
startFrom startTime;
startTime 0;
stopAt endTime;
deltaT 1;
endTime 2000;
writeControl timeStep;
writeInterval 100;
purgeWrite 0;
writeFormat ascii;
writePrecision 8;
runTimeModifiable true;
libs
(
// Needed for availability of porous baffle boundary in potentialFoam
#include "turbulenceLib"
);
wallShearStress1
{
// Mandatory entries (unmodifiable)
type wallShearStress;
libs (fieldFunctionObjects);
// Optional entries (runtime modifiable)
// patches (<patch1> ... <patchN>); // (wall1 "(wall2|wall3)");
// Optional (inherited) entries
writePrecision 8;
writeToFile true;
useUserTime true;
region region0;
enabled true;
log true;
timeStart 0;
timeEnd 1000;
executeControl timeStep;
executeInterval 1;
writeControl timeStep;
writeInterval 1;
}
// ************************************************************************* //
Code: Select all
OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.21.0.31625 (Git)
Build type: Release
Branch: master
Hash: 72df7997700062b6a02f2f208e6291f64073fb88
Python 3.10.8, Qt 5.15.6, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.3
Locale: German/Germany (de_DE)
Installed mods:
* A2plus 0.4.60i
* AirPlaneDesign 0.4.0
* Assembly4 0.11.8
* Behave-Dark-Colors 0.1.1
* CfdOF 1.21.3
* CurvedShapes 1.0.0
* Curves 0.3.0
* fasteners
* Manipulator 1.5.0
* MeshRemodel 1.8919.0
* nurbs
* Plot 2022.4.17
* POV-Ray-Rendering
* Render 2022.1.0
* Ship 2022.4.11
* Silk -1387159344.0.0